The present invention relates to a modular pallet system. Pallets are valuable components in the transport of goods, both raw materials and finished goods, and are used in nearly every facet of modern shipping, product transport, and storage. Pallets are widely used to provide a portable platform for handling, shipping, and storing materials. Materials may be placed on a pallet in one facility, shipped to and stored in another, and transported to a third without the need to load and unload the shipped material from the pallet. Further, the materials may be transported to or from a storage, shipping, or work location within a facility with minimal effort.
The most popular and widely used pallets are formed from multiple levels of transverse support elements. In one embodiment, top slabs (on which material is placed) are secured to transverse support elements that elevate the slabs from the ground. These transverse support elements may be assembled to bottom transverse slabs to complete the pallet. The transverse support elements are spaced and selected to allow forks from a lift truck to engage, elevate and transport the pallet from one location to another, with or without materials onboard. In the most popular variation of these pallets, the top and bottom slabs and transverse support elements are formed of wood.
These popular pallets are preferred because they are inexpensive to manufacture, have a reasonably long shelf life (longer if the slabs and transverse elements are made of a more durable material such as plastic), can support a great deal of weight, are interchangeable with one another, of a standard size and consistently manufactured. Pallet construction may be evaluated based on weight, cost, structural strength, versatility, ease of transportation, and reusability.
One existing problem with current pallet systems is over- or under-sized packages that may need to be transported. This problem creates a need for customized pallet construction in order to properly support and transport material.
A number of alternative pallet arrangements have been proposed, including modular pallets, plastic pallets, or pallets of different designs of the standard wooden pallet. The disadvantages of these pallets will become apparent from the following discussion of these systems.
U.S. Pat. No. 5,582,113 to Langenbeck describes a modular pallet that is constructed from molded plastic pallet members. This modular pallet may be assembled into a variety of sizes; however as can be appreciated from the various figures of the application, assembly of the various components to one another is complicated and time consuming. Further, the apparatus described by Langenbeck shows the use of “deflectable tines” useful to “secure the pallet members . . . to each other,” as shown in FIG. 10, but these tines are not easily accessible and may be difficult to operate.
U.S. Pat. No. 5,483,899 to Christie also discloses a modular pallet that may be constructed of plastic or other durable materials. This modular pallet system, like Langenbeck, utilizes interlocking sections to form a pallet. However, Christie describes separate, non-uniform sections which must be secured to one another in order to form the pallet structure. Further, like Langenbeck, the structure useful for securing various components together are deflectable tines (FIG. 5), which may be difficult to access and operate.
U.S. Pat. No. 5,809,905 to John et al. discloses a modular system that incorporates a lattice structure and interlocking elements and may be formed of plastic or other material. However, like the previous applications, John et al. describes a separate, non-integrally mounted structure (center locking ring 46, FIG. 1) to secure the modular elements to one another. Further, John et al. is not expandable beyond the predetermined size shown in the preferred arrangement.
As evident from the prior art systems, there exist problems with the current state of the art in modular pallet systems. First, there is realized a need for a modular pallet system which may be expandable beyond the standard pallet size to accommodate oversized materials. Second, there is realized a need for a modular system having an integrally mounted or integrally formed locking or latching system for securing modular pallet systems to one another. Finally, there is recognized a need for an inexpensive high-strength, low-cost pallet system which may replace or supplement existing available pallet systems.
Disclosed is an expandable modular pallet system comprising a number of elongated modules each sized to be a fraction of a desired pallet size. The modules may have a lattice array with the strength to support a load. Each module has two female tracks on a first side and male tracks on an opposite second side such that female tracks can engage male tracks of an adjacent like module and are adapted to interlock as desired to assemble a pallet of the desired size. Each module also includes at least one and usually at least two slam latches nested in the module which engage a striker on an adjacent module to lock the modules together. The slam latch may be disengaged to permit disassembly of the modules.
Each module also includes passageways to permit placing forks of a fork lift under the assembled pallet, with or without materials loaded on the pallet. Additionally, each module may include a notch adapted to enable a strap tie that extends between the first and second sides and engage a load on the pallet. The male tracks may be U-shaped with extending tabs that engage the female tracks of an adjacent module.
Each module may include three male and female tracks on opposite sides, positioned to engage complementary tracks on adjacent modules, and at least two slam latches and corresponding strikers on opposite sides, positioned to engage strikers on adjacent modules. This way a pallet system of like modules can be assembled and interlocked of a desired size. Each slam latch may be mechanically biased, for example, by a mechanical spring, to engage the striker of an adjacent module. Further, the end portions of the modules may be angular to enable the modules to nest and be stacked on one another.
As a result, a pallet system is assembled by engaging adjacent modules in an expandable modular interlocking pallet system. The modules may include a lattice structure extending between a front, back, and two sidewalls. The lattice structure supports a load on the modules. A vertical projection or stop extends from the first side and has a profile for locking the module to an adjacent module of like construction. A vertical groove extends along the second side opposite the first side and includes a profile complementary to the vertical projection for locking the module to an adjacent module. A striker is provided on one of side of the module and a slam latch is provided on the opposing side of the module with the slam latch movable between a locked position where it engages the striker of the adjacent module and an unlocked position where it disengages the striker of the adjacent module. The slam latches are also removable so that broken slam latches can be removed and replaced by new slam latches
Also disclosed is a method of assembling a modular pallet system of a desired size. The method includes providing a number of like modules, each with a first side with a male connector and opposite second side with a female connector having a stop such that adjacent modules can be assembled and interlocked. The male connector of each module is inserted into any female connector of an adjacent module until it engages the stop. A slam latch and striker are also provided on opposite sides of each module adapted to engage and lock modules in assembly of the modules in forming a pallet system. The slam latch on one side of each module engages a striker of the opposite side of an adjacent module, thereby securely locking the two adjacent modules together. A number of modules may be assembled in this manner until the pallet system of the desired size is provided.